Ethanol in aqueous hydrogen peroxide solution: Hydrothermal synthesis of highly photoluminescent carbon dots as multifunctional nanosensors

Carbon ◽  
2015 ◽  
Vol 93 ◽  
pp. 999-1007 ◽  
Author(s):  
Yaoping Hu ◽  
Jing Yang ◽  
Li Jia ◽  
Jun-Sheng Yu
1976 ◽  
Vol 31 (10) ◽  
pp. 1376-1378 ◽  
Author(s):  
G. Sosnovsky ◽  
M. Konieczny

The preparation of the key intermediate for spin labeling, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (2), was reinvestigated using sodium tungstate or phosphotungstic acid with or without either Trilon or Triton B. A two-fold and a 3.5-fold molar excess of a 30% aqueous hydrogen peroxide solution was used. The oxidation of 4-hydroxy-2,2,6,6-tetramethylpiperidine (1) with a two-fold molar excess of a 30% aqueous hydrogen peroxide solution in the presence of sodium tungstate alone, under vigorous stirring for two hours, is the superior method (A) for the preparation of 2 in virtually quantitative yield.


2012 ◽  
Vol 389 ◽  
pp. 17-24 ◽  
Author(s):  
Sagar Roy ◽  
Atsawin Thongsukmak ◽  
John Tang ◽  
Kamalesh K. Sirkar

1932 ◽  
Vol 7 (3) ◽  
pp. 270-282
Author(s):  
W. H. Hatcher ◽  
E. C. Powell

The conductivities of formic, acetic, propionic and succinic acids and succinic monoperacid have been studied in water and in aqueous hydrogen peroxide solution. These acids all add hydrogen peroxide to form un-ionized complexes which later, with time, lose water to form the so-called peracids of negligible conductivity. The formation of such complexes is dependent solely on the concentration of reagents, the peracid being produced subsequently by loss of water.


2011 ◽  
Vol 396-398 ◽  
pp. 596-599
Author(s):  
Guo Yan Luan ◽  
Wei Ping Gao ◽  
Ping Jing Yao

The technologies of ion exchange resin for ultra pure hydrogen peroxide production are more and more focused. The aim of this research was to determine suitable parameters for effective removal of Na+ impurities from aqueous hydrogen peroxide solution to produce ultra pure hydrogen peroxide. Dynamic experiments for the different operation conditions, i.e., initial concentration, flow rate, ratio of height to diameter were carried out. The concentrations of Na+ of the effluents from the ion exchange resin column were determined by ICPS-7510.The breakthrough curves of Na+ were measured and analyzed. The results shown that Na+ could be reduced effectively from the experimental aqueous hydrogen peroxide solution with the fitting conditions of ion exchange resin column, which provided the basis for determining of the suitable operating conditions of ion exchange column of a pilot plant.


Author(s):  
Anton A. Chumakov ◽  
Oleg A. Kotelnikov ◽  
Yurij G. Slizhov ◽  
Tamara S. Minakova

There are actuality and importance of confirmation or at least reasoned argumentation of molecular kinetics of hydrogen peroxide oxidation reactions because of currently unidentified true nature of oxygen intermediates, at one side, and widespread of these processes in natural biological and artificial anthropogenic systems, from other side. The building of common theory of hydrogen peroxide oxidative activity and dismutation decomposition can be based on determination of structure of individual model reactions products. The benzylpenicillin molecule has a heterofunctional structure. Its sodium salt was dissolved in aqueous hydrogen peroxide solution without Fenton catalysts addition. The system was protected from thermal and photochemical activation. As result, we observed a colloid solution formation, a water-insoluble sediment accumulation, and a hydrogen peroxide disproportionation with gas-phase molecular oxygen liberation. The NMR-spectroscopy data evidenced in favor of S-oxidation of sulfide fragment, N-oxidation of nitrogen atoms with amide groups dissociation, and aromatic ring hydroxylation and electrophilic carbonylation. The precipitate is a mixture of several substances, some of which have presumably an oligomeric structure due to neighboring molecules coupling in carbonylation and hydroxylamine fragments O-acylation reactions. The molecular kinetics of model organic molecule oxidative modifications and hydrogen peroxide dismutation is interpreted by oxywater-oxenoid conception. In accordance with one, there are different associates between water HOH and hydrogen peroxide HOOH molecules in solution system due to hydrogen bonds. These molecules are simultaneously Brønsted acids and bases. The rate of proton accepting and donation depends on temperature and concentration parameters. The hydronium H3O+ and hydroperoxonium H3O2+ cations, and the hydroxide HO− and hydroperoxide HO2− anions are generated. For hydrogen peroxide molecule H2O2, there is possibility for isomeric bipolar ion oxywater H2O+O− formation. The zwitter-ion heterolytically dissociates with water molecule liberation and singlet oxygen atom generation. The 1D-oxene (2p[↑↓][↑↓][_]) oxidizes sulfur and nitrogen heteroatoms through accepting their unshared electron pairs by own vacant atomic orbital. In addition, singlet oxygen atom hydroxylates an aromatic ring by hydride transfer and mediates decomposition of hydrogen peroxide. The dioxygen liberated during hydrogen peroxide dismutation is generated at first in singlet 1∆g-quantum state, the quenching of which, presumably, includes a dimerization of 1O2 antipodes by orbital moment. Inside the associate (1O2)2, the electron exchange interaction occurs. As result, two molecules of triplet dioxygen are generated, and they are antipodes by spin moment: first molecule has spin +1 and second molecule has spin −1.


2014 ◽  
Vol 884-885 ◽  
pp. 140-143
Author(s):  
Guo Yan Luan ◽  
Wei Ping Gao ◽  
Ping Jing Yao

The technologies of ion exchange resin for ultra pure hydrogen peroxide production are more and more focused.The aim of this research was to select suitable parmeters for effective removal of P ion impurities from the experimetal aqueous hydrogen peroxide solution to produce ultra-pure hydrogen peroxide. Dynamic experiments for the different operation conditions, i.e., initial concentrations, flow rates, ratios of height to diameter were carried out. The concentrations of P anion of the effluent samples from the anion exchange resin column were determined by ICPS-7510.The breakthrough curves of P ion were measured and analyzed. The results showed that P ion could be reduced effectively from the experimetal aqueous hydrogen peroxide solution with the fitting conditions of ion exchange resin column, It provided the basis for determining of the suitable operating conditions of ion exchange column of commercial plant.


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